Russian gold reserves are close to an all-time record
In October, Polyus Aldan JSC, the oldest gold mining enterprise of our country, set a new mining record – 5 tons of this precious metal has been produced since the beginning of the year. In connection with this, "Forpost" decided to ask Aleksey Noskov, the Managing Director of the company, a few related questions: how did they manage to yield such an impressive result, what is the effect of production increase on gold reserves of our country, when do we catch up on Australia and surpass production volumes that Australia has already reached.
Recently gold mining in Russia is on the growth trend. How does it differ from what is happening in other countries?
In 2017, 270 tons of gold were produced in our country. This is quite a good result, and, thanks to it, Russia is in the top three of world leaders in the industry. Moreover, in the foreseeable future there is a chance to overtake Australia, which currently resides at the second spot. As before, China holds the crown of leadership. According to official data, last year Chinese gold mining companies produced as much as 426 tons of gold.
Does the increase in production affect Russia’s gold reserve? How big is it exactly?
The historical record was reached in 1940. Back then gold reserves of our country amounted to 2800 tons. By 1985, gold holdings had decreased by nearly four times, and one of the lowest figures was recorded at the time of the Soviet collapse – 290 tons only. Now we are rapidly accumulating reserves. As of October, accumulated volumes of gold equal 1998.5 tons.
By having reached these levels, we managed to push China out of the top five of the countries with the largest gold reserves. Today Russia’s gold reserve is much higher than, for instance, those ones of Switzerland, Japan and India. The first spot is occupied by the US. The volume of their reserves is 8133 tons, much higher than in any other country. The United States are followed by Germany, Italy and France.
How did you manage to achieve such a significant increase in production? Did you implement some innovative decisions? As an example, adapting a heap leaching technology at the Kuranakh gold mine in Yakutia, the one you are currently developing, was considered as one of the five most significant last year’s industry events…
By international standards, the ores that we develop are very complex. Therefore, introducing the most effective processing technology for "Polyus Aldan" was a basic necessity. Before starting to produce on an industrial scale, we conducted a thorough analysis, estimated our reserves and elaborated universal solution for ore agglomeration. The latter one involves supplementing ore with special additives, such as in particular concrete, for the purpose of producing a higher quality pellet.
This year we have already received the first half a ton of gold through the use of heap leach technology. In practice it works like this – the rock is crushed to a class of 125 mm and then watered with cyanide solutions. According to the regulations, it should be leached for 2-3 months. However, a possibility of watering up to a year is being currently discussed, following the foreign countries’ example.
By applying this technology, Polyus Aldan may also produce low assay ore. Previously processing this type of ore was not financially viable, but today we extract up to 70% of gold from it and we plan to increase this figure in the future. There were few people who believed that achieving these numbers would be possible. Today these numbers are real, thanks to implementation of the investment program of the Polyus Group.
Talking about the factory itself, which is, by the way, the oldest in the country, for it was built over half a century ago, we may see some serious changes here as well. For a long time it was considered that processing 3800 tons is the limit. Over the last three years, we have implemented multiple innovations concerning crush grinding as well as sorption leaching process. As a result, we have increased processing volumes by 32%, and at the output we have 24% more gold than earlier.
Adopting the heap leaching technology allowed for using dumping sites or, in other words, production waste. Did you manage to increase proven reserves at the Kuranakh mine through the use of this technology?
Over the years, the company has accumulated about 50 million tons of so-called off-balance ore with low gold content (0.7-0.72 grams per ton). Thus, according to our estimates, there are about 37-40 tons of metal at the plant area, where it is currently stored. The heap leaching technology will actually allow us to extract gold from this ore.
What was the gold content in the past to make the production economically viable? What about the foreign countries?
At our mining plants gold grading is close to 1.2 grams per ton. As for the foreign experience, for example, in the United States it is considered cost-effective to use ore with gold grading at 0.4-0.5 grams. However, the process of leaching in this case takes a few years.
The thing is that when the dump dwells for a longer period of time and irrigation occurs only sporadically, the manufacturer may expect maximum efficiency even if the lower-grade ore is processed. In our country, the speed at which the results are achieved is often considered of higher importance than profitability. Nonetheless, I think that in the nearest future we will manage to adopt almost zero-waste technologies.